t1497f35
July 12th, 2011, 12:32 PM
Hi,
See attached video,
the Earth texture appears already rotated on the globe, though I haven't done any rotation, anyone knows why?
Here's the source code and the vert and frag shaders, texture attached.
Earth.cpp:
#include <GLTools.h>
#include <GLMatrixStack.h>
#include <GLGeometryTransform.h>
#include <GLFrame.h>
#include <GLFrustum.h>
#include <StopWatch.h>
#include <GLTriangleBatch.h>
#include <iostream>
#ifdef __APPLE__
#include <glut/glut.h>
#else
#include <GL/glut.h>
#endif
GLMatrixStack mvMatStack, projMatStack;
GLGeometryTransform transformPipe;
GLFrame cameraFrame;
GLFrustum viewFrustum;
GLTriangleBatch sphereBatch;
GLuint earthSh, texId;
GLint locAmbientColor, locDiffuseColor, locNormalMat, locMvMat, locMvpMat, locLightPos, locTexUnit;
bool LoadTGATexture(const char *name, GLenum minFilter, GLenum magFilter, GLenum wrapMode) {
int width, height, openglFormat;
GLenum imageFormat;
GLbyte *pBytes = gltReadTGABits(name, &width, &height, &openglFormat, &imageFormat);
if(pBytes == NULL) {
std::cerr << __PRETTY_FUNCTION__ << " Can't load texture " << name << std::endl;
return false;
}
glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, minFilter);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, magFilter);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, wrapMode);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, wrapMode);
glTexImage2D(GL_TEXTURE_2D, 0, openglFormat, width, height, 0, imageFormat, GL_UNSIGNED_BYTE, pBytes);
free(pBytes);
if(minFilter == GL_LINEAR_MIPMAP_LINEAR ||
minFilter == GL_LINEAR_MIPMAP_NEAREST ||
minFilter == GL_NEAREST_MIPMAP_NEAREST ||
minFilter == GL_NEAREST_MIPMAP_NEAREST) {
glGenerateMipmap(GL_TEXTURE_2D);
}
return true;
}
void ChangeSize(int w, int h) {
glViewport(0, 0, w, h);
viewFrustum.SetPerspective(35.0f, float(w)/float(h), 0.01f, 100.0f);
projMatStack.LoadMatrix(viewFrustum.GetProjectionM atrix());
transformPipe.SetMatrixStacks(mvMatStack, projMatStack);
}
void RenderScene() {
glClear(GL_DEPTH_BUFFER_BIT | GL_COLOR_BUFFER_BIT);
static CStopWatch stopWatch;
const float fNum = 0.2f;
GLfloat vAmbientColor[] = {fNum, fNum, fNum, 1.0f};
GLfloat vDiffuseColor[] = {1.0f, 1.0f, 1.0f, 1.0f};
GLfloat vLightPos[] = {-100.0f, 100.0f, 100.0f};
M3DMatrix44f cameraMat;
cameraFrame.GetCameraMatrix(cameraMat);
mvMatStack.PushMatrix();
mvMatStack.MultMatrix(cameraMat);
mvMatStack.Rotate(stopWatch.GetElapsedSeconds() * 20.0f, 0.0f, 1.0f, 0.0f);
glUseProgram(earthSh);
glUniform1i(locTexUnit, 0);
glUniform4fv(locAmbientColor, 1, vAmbientColor);
glUniform4fv(locDiffuseColor, 1, vDiffuseColor);
glUniform3fv(locLightPos, 1, vLightPos);
glUniformMatrix3fv(locNormalMat, 1, GL_FALSE, transformPipe.GetNormalMatrix());
glUniformMatrix4fv(locMvMat, 1, GL_FALSE, transformPipe.GetModelViewMatrix());
glUniformMatrix4fv(locMvpMat, 1, GL_FALSE, transformPipe.GetModelViewProjectionMatrix());
sphereBatch.Draw();
mvMatStack.PopMatrix();
glutSwapBuffers();
}
bool SetupRC() {
glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
glEnable(GL_DEPTH_TEST);
glEnable(GL_CULL_FACE);
glGenTextures(1, &texId);
glActiveTexture(GL_TEXTURE0);
glBindTexture(GL_TEXTURE_2D, texId);
if(!LoadTGATexture("Earth.tga", GL_LINEAR_MIPMAP_LINEAR, GL_LINEAR, GL_CLAMP_TO_EDGE)) {
return false;
}
gltMakeSphere(sphereBatch, 1.0f, 50, 50);
earthSh = gltLoadShaderPairWithAttributes("Earth.vert", "Earth.frag", 3, GLT_ATTRIBUTE_VERTEX, "vVertex",
GLT_ATTRIBUTE_NORMAL, "vNormal", GLT_ATTRIBUTE_TEXTURE0, "vCoords");
locAmbientColor = glGetUniformLocation(earthSh, "ambientColor");
locDiffuseColor = glGetUniformLocation(earthSh, "diffuseColor");
locNormalMat = glGetUniformLocation(earthSh, "normalMatrix");
locMvMat = glGetUniformLocation(earthSh, "mvMatrix");
locMvpMat = glGetUniformLocation(earthSh, "mvpMatrix");
locLightPos = glGetUniformLocation(earthSh, "vLightPosition");
locTexUnit = glGetUniformLocation(earthSh, "texUnit");
cameraFrame.MoveForward(-4.0f);
return true;
}
void ShutdownRC() {
glDeleteTextures(1, &texId);
glDeleteProgram(earthSh);
}
int main(int argc, char *argv[]) {
gltSetWorkingDirectory(argv[0]);
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGBA | GLUT_DEPTH);
glutInitWindowSize(800, 600);
glutCreateWindow("Rotating Earth");
glutDisplayFunc(RenderScene);
glutReshapeFunc(ChangeSize);
GLenum result = glewInit();
if(result != GLEW_OK) {
std::cout << __PRETTY_FUNCTION__ << glewGetErrorString(result) << std::endl;
return result;
}
if(!SetupRC()) {
std::cout << "setup rc failed, returning" << std::endl;
return 1;
}
atexit(ShutdownRC);
glutTimerFunc(50, gltRepaintScene, 30);
glutMainLoop();
return 0;
}
Vert shader:
#version 330
in vec4 vVertex;
in vec3 vNormal;
in vec2 vCoords;
uniform mat4 mvpMatrix;
uniform mat4 mvMatrix;
uniform mat3 normalMatrix;
uniform vec3 vLightPosition;
out vec3 vVaryingNormal;
out vec3 vVaryingLightDir;
out vec2 vPassCoords;
void main() {
vPassCoords = vCoords;
vVaryingNormal = normalMatrix * vNormal;
vec4 vEyePos4 = mvMatrix * vVertex;
vec3 vEyePos3 = vEyePos4.xyz / vEyePos4.w;
vVaryingLightDir = vLightPosition - vEyePos3;
gl_Position = mvpMatrix * vVertex;
}
Frag shader:
#version 330
uniform vec4 ambientColor;
uniform vec4 diffuseColor;
uniform sampler2D texUnit;
in vec3 vVaryingLightDir;
in vec3 vVaryingNormal;
in vec2 vPassCoords;
out vec4 vFinalColor;
void main() {
vec3 vNormal = normalize(vVaryingNormal);
vec3 vLightDir = normalize(vVaryingLightDir);
float fIntensity = max(0.0, dot(vNormal, vLightDir));
vFinalColor = diffuseColor * fIntensity;
vFinalColor += ambientColor;
vFinalColor *= texture(texUnit, vPassCoords);
vec3 vReflection = reflect(-vLightDir, vNormal);
fIntensity = max(0.0, dot(vNormal, vReflection));
if(fIntensity > 0.0f) {
float fPow = pow(fIntensity, 128.0f);
vFinalColor.rgb += vec3(fPow, fPow, fPow);
}
}
Makefile:
MAIN = Earth
SRCPATH = ../../../Src/Chapter06/$(MAIN)/
SHAREDPATH = ../../../Src/GLTools/src/
SHAREDINCPATH = ../../../Src/GLTools/include/
LIBDIRS = -L/usr/X11R6/lib -L/usr/X11R6/lib64 -L/usr/local/lib
INCDIRS = -I/usr/include -I/usr/local/include -I/usr/include/GL -I$(SHAREDINCPATH) -I$(SHAREDINCPATH)GL
CC = g++
CFLAGS = $(COMPILERFLAGS) -g $(INCDIRS)
LIBS = -lX11 -lglut -lGL -lGLU -lm
prog : $(MAIN)
$(MAIN).o : $(SRCPATH)$(MAIN).cpp
glew.o : $(SHAREDPATH)glew.c
GLTools.o : $(SHAREDPATH)GLTools.cpp
GLBatch.o : $(SHAREDPATH)GLBatch.cpp
GLTriangleBatch.o : $(SHAREDPATH)GLTriangleBatch.cpp
GLShaderManager.o : $(SHAREDPATH)GLShaderManager.cpp
math3d.o : $(SHAREDPATH)math3d.cpp
$(MAIN) : $(MAIN).o glew.o
$(CC) $(CFLAGS) -o $(MAIN) $(LIBDIRS) $(SRCPATH)$(MAIN).cpp $(SHAREDPATH)glew.c $(SHAREDPATH)GLTools.cpp $(SHAREDPATH)GLBatch.cpp $(SHAREDPATH)GLTriangleBatch.cpp $(SHAREDPATH)GLShaderManager.cpp $(SHAREDPATH)math3d.cpp $(LIBS)
clean:
rm -f *.o
Example derived from the OpenGL Superbible 5th ed.
See attached video,
the Earth texture appears already rotated on the globe, though I haven't done any rotation, anyone knows why?
Here's the source code and the vert and frag shaders, texture attached.
Earth.cpp:
#include <GLTools.h>
#include <GLMatrixStack.h>
#include <GLGeometryTransform.h>
#include <GLFrame.h>
#include <GLFrustum.h>
#include <StopWatch.h>
#include <GLTriangleBatch.h>
#include <iostream>
#ifdef __APPLE__
#include <glut/glut.h>
#else
#include <GL/glut.h>
#endif
GLMatrixStack mvMatStack, projMatStack;
GLGeometryTransform transformPipe;
GLFrame cameraFrame;
GLFrustum viewFrustum;
GLTriangleBatch sphereBatch;
GLuint earthSh, texId;
GLint locAmbientColor, locDiffuseColor, locNormalMat, locMvMat, locMvpMat, locLightPos, locTexUnit;
bool LoadTGATexture(const char *name, GLenum minFilter, GLenum magFilter, GLenum wrapMode) {
int width, height, openglFormat;
GLenum imageFormat;
GLbyte *pBytes = gltReadTGABits(name, &width, &height, &openglFormat, &imageFormat);
if(pBytes == NULL) {
std::cerr << __PRETTY_FUNCTION__ << " Can't load texture " << name << std::endl;
return false;
}
glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, minFilter);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, magFilter);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, wrapMode);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, wrapMode);
glTexImage2D(GL_TEXTURE_2D, 0, openglFormat, width, height, 0, imageFormat, GL_UNSIGNED_BYTE, pBytes);
free(pBytes);
if(minFilter == GL_LINEAR_MIPMAP_LINEAR ||
minFilter == GL_LINEAR_MIPMAP_NEAREST ||
minFilter == GL_NEAREST_MIPMAP_NEAREST ||
minFilter == GL_NEAREST_MIPMAP_NEAREST) {
glGenerateMipmap(GL_TEXTURE_2D);
}
return true;
}
void ChangeSize(int w, int h) {
glViewport(0, 0, w, h);
viewFrustum.SetPerspective(35.0f, float(w)/float(h), 0.01f, 100.0f);
projMatStack.LoadMatrix(viewFrustum.GetProjectionM atrix());
transformPipe.SetMatrixStacks(mvMatStack, projMatStack);
}
void RenderScene() {
glClear(GL_DEPTH_BUFFER_BIT | GL_COLOR_BUFFER_BIT);
static CStopWatch stopWatch;
const float fNum = 0.2f;
GLfloat vAmbientColor[] = {fNum, fNum, fNum, 1.0f};
GLfloat vDiffuseColor[] = {1.0f, 1.0f, 1.0f, 1.0f};
GLfloat vLightPos[] = {-100.0f, 100.0f, 100.0f};
M3DMatrix44f cameraMat;
cameraFrame.GetCameraMatrix(cameraMat);
mvMatStack.PushMatrix();
mvMatStack.MultMatrix(cameraMat);
mvMatStack.Rotate(stopWatch.GetElapsedSeconds() * 20.0f, 0.0f, 1.0f, 0.0f);
glUseProgram(earthSh);
glUniform1i(locTexUnit, 0);
glUniform4fv(locAmbientColor, 1, vAmbientColor);
glUniform4fv(locDiffuseColor, 1, vDiffuseColor);
glUniform3fv(locLightPos, 1, vLightPos);
glUniformMatrix3fv(locNormalMat, 1, GL_FALSE, transformPipe.GetNormalMatrix());
glUniformMatrix4fv(locMvMat, 1, GL_FALSE, transformPipe.GetModelViewMatrix());
glUniformMatrix4fv(locMvpMat, 1, GL_FALSE, transformPipe.GetModelViewProjectionMatrix());
sphereBatch.Draw();
mvMatStack.PopMatrix();
glutSwapBuffers();
}
bool SetupRC() {
glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
glEnable(GL_DEPTH_TEST);
glEnable(GL_CULL_FACE);
glGenTextures(1, &texId);
glActiveTexture(GL_TEXTURE0);
glBindTexture(GL_TEXTURE_2D, texId);
if(!LoadTGATexture("Earth.tga", GL_LINEAR_MIPMAP_LINEAR, GL_LINEAR, GL_CLAMP_TO_EDGE)) {
return false;
}
gltMakeSphere(sphereBatch, 1.0f, 50, 50);
earthSh = gltLoadShaderPairWithAttributes("Earth.vert", "Earth.frag", 3, GLT_ATTRIBUTE_VERTEX, "vVertex",
GLT_ATTRIBUTE_NORMAL, "vNormal", GLT_ATTRIBUTE_TEXTURE0, "vCoords");
locAmbientColor = glGetUniformLocation(earthSh, "ambientColor");
locDiffuseColor = glGetUniformLocation(earthSh, "diffuseColor");
locNormalMat = glGetUniformLocation(earthSh, "normalMatrix");
locMvMat = glGetUniformLocation(earthSh, "mvMatrix");
locMvpMat = glGetUniformLocation(earthSh, "mvpMatrix");
locLightPos = glGetUniformLocation(earthSh, "vLightPosition");
locTexUnit = glGetUniformLocation(earthSh, "texUnit");
cameraFrame.MoveForward(-4.0f);
return true;
}
void ShutdownRC() {
glDeleteTextures(1, &texId);
glDeleteProgram(earthSh);
}
int main(int argc, char *argv[]) {
gltSetWorkingDirectory(argv[0]);
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGBA | GLUT_DEPTH);
glutInitWindowSize(800, 600);
glutCreateWindow("Rotating Earth");
glutDisplayFunc(RenderScene);
glutReshapeFunc(ChangeSize);
GLenum result = glewInit();
if(result != GLEW_OK) {
std::cout << __PRETTY_FUNCTION__ << glewGetErrorString(result) << std::endl;
return result;
}
if(!SetupRC()) {
std::cout << "setup rc failed, returning" << std::endl;
return 1;
}
atexit(ShutdownRC);
glutTimerFunc(50, gltRepaintScene, 30);
glutMainLoop();
return 0;
}
Vert shader:
#version 330
in vec4 vVertex;
in vec3 vNormal;
in vec2 vCoords;
uniform mat4 mvpMatrix;
uniform mat4 mvMatrix;
uniform mat3 normalMatrix;
uniform vec3 vLightPosition;
out vec3 vVaryingNormal;
out vec3 vVaryingLightDir;
out vec2 vPassCoords;
void main() {
vPassCoords = vCoords;
vVaryingNormal = normalMatrix * vNormal;
vec4 vEyePos4 = mvMatrix * vVertex;
vec3 vEyePos3 = vEyePos4.xyz / vEyePos4.w;
vVaryingLightDir = vLightPosition - vEyePos3;
gl_Position = mvpMatrix * vVertex;
}
Frag shader:
#version 330
uniform vec4 ambientColor;
uniform vec4 diffuseColor;
uniform sampler2D texUnit;
in vec3 vVaryingLightDir;
in vec3 vVaryingNormal;
in vec2 vPassCoords;
out vec4 vFinalColor;
void main() {
vec3 vNormal = normalize(vVaryingNormal);
vec3 vLightDir = normalize(vVaryingLightDir);
float fIntensity = max(0.0, dot(vNormal, vLightDir));
vFinalColor = diffuseColor * fIntensity;
vFinalColor += ambientColor;
vFinalColor *= texture(texUnit, vPassCoords);
vec3 vReflection = reflect(-vLightDir, vNormal);
fIntensity = max(0.0, dot(vNormal, vReflection));
if(fIntensity > 0.0f) {
float fPow = pow(fIntensity, 128.0f);
vFinalColor.rgb += vec3(fPow, fPow, fPow);
}
}
Makefile:
MAIN = Earth
SRCPATH = ../../../Src/Chapter06/$(MAIN)/
SHAREDPATH = ../../../Src/GLTools/src/
SHAREDINCPATH = ../../../Src/GLTools/include/
LIBDIRS = -L/usr/X11R6/lib -L/usr/X11R6/lib64 -L/usr/local/lib
INCDIRS = -I/usr/include -I/usr/local/include -I/usr/include/GL -I$(SHAREDINCPATH) -I$(SHAREDINCPATH)GL
CC = g++
CFLAGS = $(COMPILERFLAGS) -g $(INCDIRS)
LIBS = -lX11 -lglut -lGL -lGLU -lm
prog : $(MAIN)
$(MAIN).o : $(SRCPATH)$(MAIN).cpp
glew.o : $(SHAREDPATH)glew.c
GLTools.o : $(SHAREDPATH)GLTools.cpp
GLBatch.o : $(SHAREDPATH)GLBatch.cpp
GLTriangleBatch.o : $(SHAREDPATH)GLTriangleBatch.cpp
GLShaderManager.o : $(SHAREDPATH)GLShaderManager.cpp
math3d.o : $(SHAREDPATH)math3d.cpp
$(MAIN) : $(MAIN).o glew.o
$(CC) $(CFLAGS) -o $(MAIN) $(LIBDIRS) $(SRCPATH)$(MAIN).cpp $(SHAREDPATH)glew.c $(SHAREDPATH)GLTools.cpp $(SHAREDPATH)GLBatch.cpp $(SHAREDPATH)GLTriangleBatch.cpp $(SHAREDPATH)GLShaderManager.cpp $(SHAREDPATH)math3d.cpp $(LIBS)
clean:
rm -f *.o
Example derived from the OpenGL Superbible 5th ed.